GPS with Sierra Wireless, Incorporated Sierra Wireless EM7455 Qualcomm Snapdragon X7 LTE-A (cdc-wdm0)

[Angelo Corsaro]

Hi Aleksander,
something changed, now I can see the 3GPP position, but the GPS stream 
is always corrupted:

mmcli -m 0  --location-get
   --------------------------
   3GPP |      operator code: 222
        |      operator name: 50
        | location area code: 86E9
        | tracking area code: 0000
        |            cell id: 01D0DA11
   --------------------------
   GPS  |               nmea: ¤ÅAΦUiΔΠ,,1aBéØΠ,X0aBEΓΩ5f4P
        |                     ¤ÅA:t(ΔΠ,X0aBéøΠ,X0aBéØΠ*lXi
        |                     ¤ÅA2Ej_Π,(1aRÇØΠNX0YDEΓΩ2ù5P
Λ      |                     ¤ÅA:4*ΔΠAXDaBéØΠ,X0aBéØΠ,X0a"%L"


As I remember, I put NetworkManager and ModemManager in debug mode and I 
got this (only two blocks as example):


<<<<<< RAW:
<<<<<<   length = 90
<<<<<<   data   = 
01:59:00:80:10:02:04:C9:00:26:00:4D:00:01:4A:00:24:47:50:52:4D:43:2C:31:34:33:30:35:37:2E:30:2C:41:2C:34:31:34:31:2E:34:32:38:36:30:36:2C:4E:2C:30:31:32:33:37:2E:34:35:38:37:37:37:2C:45:2C:30:2E:30:2C:30:2E:30:2C:32:30:30:35:32:30:2C:30:2E:36:2C:45:2C:41:2A:30:35:0D:0A
ModemManager[8348]: [/dev/cdc-wdm0] received generic indication 
(translated)...
<<<<<< QMUX:
<<<<<<   length  = 89
<<<<<<   flags   = 0x80
<<<<<<   service = "loc"
<<<<<<   client  = 2
<<<<<< QMI:
<<<<<<   flags       = "indication"
<<<<<<   transaction = 201
<<<<<<   tlv_length  = 77
<<<<<<   message     = "NMEA" (0x0026)
<<<<<< TLV:
<<<<<<   type       = "NMEA String" (0x01)
<<<<<<   length     = 74
<<<<<<   value      = 
24:47:50:52:4D:43:2C:31:34:33:30:35:37:2E:30:2C:41:2C:34:31:34:31:2E:34:32:38:36:30:36:2C:4E:2C:30:31:32:33:37:2E:34:35:38:37:37:37:2C:45:2C:30:2E:30:2C:30:2E:30:2C:32:30:30:35:32:30:2C:30:2E:36:2C:45:2C:41:2A:30:35:0D:0A
<<<<<<   translated = 䜤剐䍍ㄬ㌴㔰⸷ⰰⱁㄴㄴ㐮㠲〶ⰶⱎ㄰㌲⸷㔴㜸㜷䔬〮〮〬〬㈬〰㈵ⰰ⸰ⰶⱅ⩁㔰਍
ModemManager[8348]: <debug> [1589985057.346975] [NMEA] 
䜤剐䍍ㄬ㌴㔰⸷ⰰⱁㄴㄴ㐮㠲〶ⰶⱎ㄰㌲⸷㔴㜸㜷䔬〮〮〬〬㈬〰㈵ⰰ⸰ⰶⱅ⩁㔰਍



ModemManager[8348]: [/dev/cdc-wdm0] received message...
<<<<<< RAW:
<<<<<<   length = 59
<<<<<<   data   = 
01:3A:00:80:10:02:04:CA:00:26:00:2E:00:01:2B:00:24:47:50:47:53:41:2C:41:2C:32:2C:31:30:2C:31:36:2C:2C:2C:2C:2C:2C:2C:2C:2C:2C:2C:31:2E:38:2C:31:2E:36:2C:30:2E:39:2A:33:32:0D:0A
ModemManager[8348]: [/dev/cdc-wdm0] received generic indication 
(translated)...
<<<<<< QMUX:
<<<<<<   length  = 58
<<<<<<   flags   = 0x80
<<<<<<   service = "loc"
<<<<<<   client  = 2
<<<<<< QMI:
<<<<<<   flags       = "indication"
<<<<<<   transaction = 202
<<<<<<   tlv_length  = 46
<<<<<<   message     = "NMEA" (0x0026)
<<<<<< TLV:
<<<<<<   type       = "NMEA String" (0x01)
<<<<<<   length     = 43
<<<<<<   value      = 
24:47:50:47:53:41:2C:41:2C:32:2C:31:30:2C:31:36:2C:2C:2C:2C:2C:2C:2C:2C:2C:2C:2C:31:2E:38:2C:31:2E:36:2C:30:2E:39:2A:33:32:0D:0A
Π0ÖdQ2FLùtranslated = ¤ÅA:4*ΔΠAXHaΦùøΠ1l0aBéØΠ,X0aBéKΣ.p0ÇcE

Π0ÖdQ2FLùger[8348]: <debug> [1589985057.411177] [NMEA] 
¤ÅA:4*ΔΠAXHaΦùøΠ1l0aBéØΠ,X0aBéKΣ.p0ÇcE




Il 20/05/20 13:36, Aleksander Morgado ha scritto:
> Hey,
>
>> I'm trying to get the GPS data from my modem, but I receive "strange"
>> character as output:
>>
>> mmcli -m 0  --location-status
>>     --------------------------------
>>     Location |         capabilities: 3gpp-lac-ci, gps-raw, gps-nmea,
>> agps-msa, agps-msb
>>              |              enabled: 3gpp-lac-ci, gps-nmea
>>              |              signals: no
>>     --------------------------------
>>     GPS      |         refresh rate: 3600 seconds
>>              | supported assistance: xtra
>>              |   assistance servers:
>> http://xtrapath2.izatcloud.net/xtra3grc.bin
>>              | http://xtrapath3.izatcloud.net/xtra3grc.bin
>>              | http://xtrapath1.izatcloud.net/xtra3grc.bin
>>
>>
>> mmcli -m 0  --location-get
>>     -----------
>>     GPS | nmea: ¤ÅAΦUiΔΠ,,1aBéØΠ,X0aBEΓΩ5f4P
>>         |       ¤ÅA:t(ΔΠ,X0aBéøΠ,X0aBéØΠ*lXi
>>         |       ¤ÅA2Ej_Π,(1aRÇØΠNX0YDEΓΩ2ù5P
>> Λ     |       ¤ÅA:4*ΔΠAXDaBéØΠ,X0aBéØΠ,X0a"%L"
>>
>>
>> mmcli -m 0  --location-get
>>     -----------
>>     GPS | nmea: ¤ÅA2Ej_Π,(1aRÇØΠNX0YDEΓΩ2ù5P
>> Ξ,TÖ1SAøΞ,¿ÖaΦ&ÅA:4JΩΠ4XHaΦføΠ1h0_ΓùØΘ6h0aΦùÅΠ1j0Ç¥'øΠ,dDaΦf
>>         |       ¤ÅAΦUiΔΠ,,1aBéØΠ,X0aBEΓΩ5f4P
>>         |
>> ¤ÅA:4JΩΠ3XLaΦFøΠ2l0£cùØΘ9b0a"&ÅΠ7n0_cFøΠ,fDa2ùÅΠ3¿XaBeøΘ,bPa"ùMΣ,TÖ£SA
>> Λ     |       ¤ÅA:4*ΔΠAXDaBéØΠ,X0aBéØΠ,X0a"%L"
>>         |       ¤ÅA:t(ΔΠ,X0aBéøΠ,X0aBéØΠ*lXi
>> Ξ,TÖΘSALΞ,lXa$FÅA:4JΩΠ3XHaΦFøΠ1p0ÇSùKΣ8b0a"&øΠ1n0Ç¥'
>> Ξ,TÖ£SAøΞ,dDa"FÅA:4JΩΠ3XDaΦFøΠ0j0£#ùØΣ9h0a$F
>> Θ,TÖ!TALÆ,nÖa"FÅA:4JΩΠ4XLaΦføΠ2h0£sùKΣ5h0a"&
>> Π1pDaBELΣ,bÖaΦùNΞ,TÖ1TAXHaΦføΠ1d0ΘsùØΣ8n0aΦù
>>
>> Under the item "Info" the modem-manager-gui in the network I can see the
>> operator (Iliad), the operator code (22250) and so on, but under the
>> Location item both the 3GPP (0/0/0/0/0) and the GPS location
>> (0,000/0,000/0,000) are empty.
>>
>> SO Linux Ubuntu 20.04, mmcli 1.12.8
>>
> Please update to libqmi to 1.24.12, I believe this issue happens due
> to the CRLF on the NMEA traces being filtered out, and so libqmi
> attempts to parse the string with a different encoding.
>